Dynamic multiplexer configuration process

ABSTRACT

A method of dynamically configuring a multiplexer that can support more frequency bands than a traditional multiplexer is disclosed. For example, the reconfigurable multiplexer can handle frequencies of several hundred megahertz up to 10 gigahertz. Further, certain implementations of the method enable the multiplexer to reduce or eliminate frequency dead zones that exist with traditional multiplexers. The reconfigurable multiplexer includes a filter bank capable of supporting a number of frequency bands and a bypass circuit that enables the multiplexer to support a variety of sets of frequencies. For instance, unlike traditional multiplexers, the reconfigurable multiplexer can support both frequency bands with relatively narrow spacing and frequency bands with relatively wide spacing. Further, the inclusion of the bypass circuit enables the reduction or elimination of dead zones between supported frequencies.

RELATED APPLICATIONS

This disclosure claims priority to U.S. Provisional Application No.62/263,428, which was filed on Dec. 4, 2015 and is titled“RECONFIGURABLE MULTIPLEXER,” U.S. Provisional Application No.62/263,625, which was filed on Dec. 5, 2015 and is titled“RECONFIGURABLE MULTIPLEXER,” and U.S. Provisional Application No.62/350,355, which was filed on Jun. 15, 2016 and is titled “MULTI-STAGERECONFIGURABLE TRIPLEXER,” the disclosures of which are expresslyincorporated by reference herein in their entirety for all purposes.Further, this application incorporates by reference, in their entiretyand for all purposes, U.S. application Ser. No. ______, which was filedon Dec. 1, 2016 and is titled “RECONFIGURABLE MULTIPLEXER,” and U.S.application Ser. ______, which was filed on Dec. 1, 2016 and is titled“MULTI-STAGE RECONFIGURABLE TRIPLEXER.” Any and all applications, ifany, for which a foreign or domestic priority claim is identified in theApplication Data Sheet of the present application are herebyincorporated by reference in their entireties under 37 CFR 1.57.

BACKGROUND

Technical Field

This disclosure relates to multiplexers and, in particular, to areconfigurable multiplexer.

Description of Related Technology

Often, wireless communication involves sending and receiving signalsalong a particular communication band. However, in some cases, wirelesscommunication may involve the use of multiple communication bands, whichis sometimes referred to as multiband communication and may involvemultiband signal processing. Usually, when a wireless device receives amultiband signal, the wireless device will perform carrier aggregationto aggregate the constituent signals. This can result in a widerbandwidth and it can be possible to receive data or communicationsignals at a higher data rate.

BRIEF DESCRIPTION OF THE DRAWINGS

Throughout the drawings, reference numbers are re-used to indicatecorrespondence between referenced elements. The drawings are provided toillustrate embodiments of the inventive subject matter described hereinand not to limit the scope thereof.

FIG. 1 illustrates a block diagram of an embodiment of a wireless devicethat includes a transceiver.

FIG. 2A illustrates a block diagram of an embodiment of a front-endmodule that includes the transceiver of FIG. 1.

FIG. 2B illustrates a block diagram of an alternative or additionalarrangement of a front-end module that includes the transceiver of FIG.1.

FIG. 3 illustrates a block diagram of an embodiment of the multiplexerof FIG. 2A or 2B.

FIG. 4A illustrates a block diagram of another embodiment of themultiplexer of FIG. 2A or 2B.

FIG. 4B illustrates example circuits that may be used as load circuitsfor the multiplexer of FIG. 4A.

FIG. 5 presents a flowchart of an embodiment of a dynamic multiplexerconfiguration process.

FIG. 6 presents a flowchart of an embodiment of a second dynamicmultiplexer configuration process.

FIG. 7A illustrates a block diagram of an embodiment of a triplexer thatmay serve as an alternative to the multiplexer of FIG. 2A and FIG. 2B.

FIG. 7B illustrates a block diagram of a second embodiment of thetriplexer of FIG. 7A.

FIG. 7C illustrates a block diagram of a third embodiment of thetriplexer of FIG. 7A.

FIG. 7D illustrates a block diagram of a fourth embodiment of thetriplexer of FIG. 7A.

FIG. 7E illustrates a block diagram of a fifth embodiment of thetriplexer of FIG. 7A.

FIG. 8 presents a flowchart of an embodiment of a dynamic multi-stagemultiplexer configuration process.

SUMMARY

The systems, methods and devices of this disclosure each have severalinnovative aspects, no single one of which is solely responsible for theall of the desirable attributes disclosed herein. Details of one or moreimplementations of the subject matter described in this specificationare set forth in the accompanying drawings and the description below.

Certain aspects of the present disclosure relate to a method ofdynamically configuring a multiplexer. The method may include receivinga control signal from a base station. This control signal may identifyat least one communication frequency. Further, the method may includedetermining whether the control signal identifies a plurality ofcommunication frequencies. In response to determining that the controlsignal identifies the plurality of communication frequencies, the methodmay include configuring a filter bank of the multiplexer based at leastin part on the plurality of communication frequencies. The filter bankmay include a plurality of filters. Further, the method may includedetermining whether the plurality of communication frequencies areassociated with a set of special carrier aggregation bands. In responseto determining that the plurality of communication frequencies areassociated with the set of special carrier aggregation bands, the methodmay include selecting a load circuit from a plurality of load circuitsincluded in the multiplexer based on the plurality of communicationfrequencies and connecting a bypass path included in the multiplexer tothe load circuit.

Configuring the filter bank may include accessing a lookup table toidentify switch configurations for a switch bank of the multiplexer andconfiguring the switch bank based on the identified switchconfigurations. Further, in response to determining that the pluralityof communication frequencies are associated with the set of specialcarrier aggregation bands, the method may further include disconnectinga remainder of additional bypass paths included in the multiplexer. Insome cases, the set of special carrier aggregation bands include aplurality of frequency bands with less than a threshold frequencyspacing between the bands. The threshold frequency spacing may beapproximately 150 megahertz. Other threshold frequency spacings arepossible. For example, the threshold frequency spacing may be 100megahertz, 200 megahertz, 500 megahertz, and the like.

In certain implementations, in response to determining that the controlsignal identifies the plurality of communication frequencies, the methodfurther includes determining whether the plurality of communicationfrequencies are associated with a set of common carrier aggregationbands. In response to determining that the plurality of communicationfrequencies are associated with the set of common carrier aggregationbands, the method includes disconnecting the bypass path. The set ofcommon carrier aggregation bands may include a plurality of frequencybands with greater than a threshold frequency spacing between the bands.Further, the threshold frequency spacing may be approximately 150megahertz. As previously discussed, other threshold frequency spacingsare possible. In some cases, the set of common carrier aggregation bandsinclude a plurality of frequency bands with an isolation requirement ofapproximately 20 decibels. In some embodiments, the isolationrequirement may be less than or greater than 20 decibels.

In response to determining that the control signal identifies a singlecommunication frequency, the method may further include connecting afirst filter corresponding to the single communication frequency fromthe filter bank to an output port of the multiplexer and disconnectingremaining signal paths within the multiplexer. The remaining signalpaths may include a first signal path that includes a second filter thatdoes not correspond to the single communication frequency and a secondsignal path that corresponds to the bypass path. Moreover, in responseto determining that the control signal identifies an unsupported signal,the method may further include deactivating the filter bank andconnecting the bypass path to an output port of the multiplexer.Further, the method may include disconnecting remaining bypass paths ofthe multiplexer.

Other aspects of the present disclosure relate to a method ofdynamically configuring a multi-stage multiplexer. The method mayinclude receiving at a multiplexer a control signal from a basebandprocessor. The control signal may identify a frequency band. Further,the method may include configuring a filter bank of the multiplexerbased at least in part on the control signal. Configuring the filterbank may include configuring a first filter stage of the filter bankbased at least in part on the frequency band and configuring a secondfilter stage of the filter bank based at least in part on the frequencyband. The first filter stage may be configured to filter a signal toobtain a partially filtered signal. Further, the second filter stage maybe configured to filter the partially filtered signal to obtain afiltered signal of the frequency band. The method may further includeconfiguring a bypass circuit of the multiplexer based at least in parton the control signal.

In some cases, the control signal is based on a second control signalreceived from a base station. Further, the bypass circuit may be part ofthe second filter stage. Moreover, the method may further includedetermining based at least in part on the control signal whether themultiplexer is to operate in a carrier aggregation mode. In response todetermining that the multiplexer is to operate in a carrier aggregationmode, configuring the bypass circuit may further include disconnectingthe bypass circuit from an operational signal path of the filter bank.Alternatively, in response to determining that the multiplexer is tooperate in a carrier aggregation mode, configuring the bypass circuitmay include connecting the bypass circuit to a filter from the firstfilter stage.

In response to determining based at least in part on the control signalthat the multiplexer is to operate in a bypass mode, configuring thesecond filter stage may include disconnecting the second filter stagefrom the first filter stage. Further, the method may include selecting aset of load circuits from a plurality of available load circuitsincluded in the multiplexer based at least in part on the control signaland connecting a set of filter output paths from the filter bank to theset of load circuits.

Certain aspects of the present disclosure relate to a multiplexer. Themultiplexer may include a filter bank that includes a plurality offilters. Further, the multiplexer may include a bypass circuit thatincludes at least one bypass path between an input of the multiplexerand an output of the multiplexer. This bypass path may not include thefilter bank. Moreover, the multiplexer may also include a first switchthat electrically connects a filter from the plurality of filters basedat least in part on a control signal and a second switch thatelectrically connects the at least one bypass path based at least inpart on the control signal.

In addition, the multiplexer may include a plurality of load circuits.In some cases, the first switch is configured to electrically connectthe filter to a load circuit from the plurality of load circuits basedat least in part on the control signal. Further, at least two loadcircuits from the plurality of load circuits may be selectable by thefirst switch to be electrically connected to the filter and the loadcircuit is selected from the at least two load circuits based at leastin part on the control signal. Additionally, the second switch may beconfigured to electrically connect the at least one bypass path to aload circuit from the plurality of load circuits based at least in parton the control signal. At least two load circuits from the plurality ofload circuits may be selectable by the second switch to be electricallyconnected to the bypass path and the load circuit may be selected fromthe at least two load circuits based at least in part on the controlsignal. In some implementations, at least one load circuit from theplurality of load circuits includes an LC circuit.

Further, in some implementations, the first switch is configured toelectrically connect the filter to an antenna based at least in part onthe control signal. Moreover, the second switch may be configured toelectrically connect the bypass path to an antenna based at least inpart on the control signal. The bypass circuit may include a phase shiftnetwork. Alternatively, or in addition, the bypass circuit may include atransmission line. In some cases, the plurality of filters may includeat least one high pass filter, band pass filter, or low pass filter.

Other aspects of the present disclosure relate to a transceiver. Thistransceiver may include a power amplifier module and a multiplexer. Thepower amplifier module may include a plurality of power amplifiers. Themultiplexer may include a filter bank that includes a plurality offilters, a bypass circuit, a first switch, and a second switch. Thebypass circuit may include at least one bypass path between an input ofthe multiplexer and an output of the multiplexer. The bypass pathgenerally does not include the filter bank within the signal path. Thefirst switch may electrically connect a filter from the plurality offilters based at least in part on a control signal. The second switchmay electrically connect the at least one bypass path based at least inpart on the control signal.

Further, the multiplexer may include a plurality of load circuits. Insome such cases, the first switch may be configured to electricallyconnect the filter to a load circuit from the plurality of load circuitsbased at least in part on the control signal. The first switch mayselect the load circuit to electrically connect to the filter from atleast two load circuits capable of being electrically connected to thefilter. With some implementations, the second switch may be configuredto electrically connect the at least one bypass path to a load circuitfrom the plurality of load circuits based at least in part on thecontrol signal. The second switch may select the load circuit toelectrically connect to the bypass path from at least two load circuitscapable of being electrically connected to the bypass path.

Yet other aspects of the present disclose relate to a wireless device.The wireless device may include a transceiver and a baseband processor.The transceiver may include a power amplifier module and a multiplexer.The power amplifier module may include a plurality of power amplifiersand the multiplexer may be in communication with the power amplifiermodule. The multiplexer may include a filter bank that includes aplurality of filters, a bypass circuit, a first switch, and a secondswitch. The bypass circuit may include at least one bypass path betweenan input of the multiplexer and an output of the multiplexer. Generally,the bypass path does not include the filter bank. The first switch maybe electrically connected to a filter from the plurality of filtersbased at least in part on a control signal. The second switch may beelectrically connected to the at least one bypass path based at least inpart on the control signal. Further, the baseband processor may beconfigured to provide the control signal to the multiplexer. The controlsignal may be determined based at least in part on a communication froma base station.

In some embodiments, the multiplexer further includes a load circuit inelectrical communication with one of the filter or the bypass path. Theload circuit may be configured to increase isolation of a signalreceived by the multiplexer.

Certain aspects of the present disclosure relate to a triplexer. Thetriplexer may include a first filter bank that includes one or morefilters. The first filter bank may be in communication with an inputport of the triplexer. The second filter bank may include one or morefilters and may be positioned between the first filter bank and a switchbank. The switch bank may include a plurality of switches that connectthe one or more filters of the second filter bank to a load circuit froma plurality of load circuits. Further, the triplexer may include abypass circuit that includes at least one bypass path between the firstfilter bank and the switch bank enabling a signal to bypass the secondfilter bank.

In some embodiments, the first filter bank includes a low pass filterand a high pass filter. Further, the second filter bank may include alow pass filter and a high pass filter. In some cases, at least onefilter of the first filter bank and at least one filter of the secondfilter bank are connected in cascade. Moreover, in some cases, the firstfilter bank and the second filter bank do not include a band passfilter. In some implementations, the first filter bank and the secondfilter bank are connected in series with one or more additional filterbank stages.

The triplexer may, in some implementations, include the plurality ofload circuits. Further, the switch bank may selectively connect a filterfrom the second filter bank to the load circuit from the plurality ofload circuits based at least in part on a control signal from a basebandprocessor. Moreover, the triplexer may include a bypass switch betweenthe first filter bank and the bypass circuit. This bypass switch may beclosed when a non-carrier aggregation signal is received.

With some implementations, a first filter from the first filter bank maybe connected to the switch bank without being connected to the secondfilter bank and a second filter from the first filter bank may beconnected to the second filter bank. Moreover, the triplexer may includea second bypass circuit. The bypass circuit may be configured withrespect to a first frequency band and the second bypass circuit may beconfigured with respect to a second frequency band. In some cases, thebypass circuit is a phase shift network.

In addition, the triplexer may include a plurality of input portsincluding the input port. Each input port, or at least some of the inputports, of the plurality of input ports may be configured to receive asignal of a different frequency band.

Other aspects of the present disclosure relate to a transceiver. Thetransceiver may include a power amplifier module that includes aplurality of power amplifiers and a triplexer in communication with thepower amplifier module. The triplexer may include a first filter bank, asecond filter bank, a switch bank, and a bypass circuit. The firstfilter bank may be in communication with an input port and may includeone or more filters. The second filter bank may be positioned betweenthe first filter bank and the switch bank and may include one or morefilters. The switch bank may include a plurality of switches thatconnect the one or more filters of the second filter bank to a loadcircuit from a plurality of load circuits. Further, the bypass circuitmay include at least one bypass path between the first filter bank andthe switch bank enabling a signal to bypass the second filter bank.

In certain embodiments, the plurality of load circuits includes a firstset of load circuits selectively connectable to the bypass circuit basedon a control signal. Further, the plurality of load circuits may includea second set of load circuits selectively connectable to the secondfilter bank based on a control signal. At least one filter of the firstfilter bank may be connected in series with at least one filter of thesecond filter bank. Further, the first filter bank and the second filterbank may omit a band pass filter.

Yet other aspects of the present disclosure relate to a wireless device.The wireless device may include a transceiver and a baseband processor.The transceiver may include a power amplifier module and a triplexer.The power amplifier module may include a plurality of power amplifiers.Further, the triplexer may be in communication with the power amplifiermodule. Moreover, the triplexer may include a first filter bank, asecond filter bank, a switch bank, and a bypass circuit. The firstfilter bank may be in communication with an input port of the triplexerand may include one or more filters. The second filter bank may bepositioned between the first filter bank and the switch bank, and mayinclude one or more filters. The switch bank may include a plurality ofswitches that selectively connect the one or more filters of the secondfilter bank to a load circuit from a plurality of load circuits based ona control signal. The bypass circuit may include at least one bypasspath between the first filter bank and the switch bank enabling a signalto bypass the second filter bank. Further, the baseband processor may beconfigured to provide the control signal to the triplexer. The controlsignal may be determined based at least in part on a communication froma base station.

Although certain embodiments and examples are disclosed herein,inventive subject matter extends beyond the examples in the specificallydisclosed embodiments to other alternative embodiments and/or uses, andto modifications and equivalents thereof.

DETAILED DESCRIPTION Introduction

Some wireless devices support communication over multiple radiofrequency (RF) bands. In some cases, a wireless device may communicateover multiple frequency or RF bands at the same time. Communicating overmultiple frequency bands may include a wireless device transmitting dataand/or voice (e.g., audio data) synchronously over multiplecommunication bands. This synchronous or simultaneous transmission overmultiple RF bands may be referred to as uplink carrier aggregation orcarrier aggregation uplink (“CAUL”). Using CAUL may enable transmissionat higher data rates because, for example, each carrier may transmitsome of the data. Thus, for example, in some cases, instead of a singlecarrier transmitting data at rate X, two carriers can transmit datatogether at a rate of up to 2X. Devices that are capable of CAULtypically include at least two power amplifiers transmitting signals atthe same time. The signals may be combined and transmitted together overa single communication connection using, for example, time divisionduplex (TDD) communication, which can communicate both carriers togetherover a single uplink connection.

Not only can some devices transmit over multiple bands, but some devicesmay also receive communications over multiple frequency or RF bands.Such devices may include multiple low noise amplifiers (LNA) that arecapable of amplifying particular frequency bands of the receivedmultiple frequency signal. Wireless devices that support carrieraggregation often include a multiplexer to facilitate the aggregationprocess. Typically, the multiplexer is a bidirectional multiplexer andmay be capable of supporting both uplink and downlink carrieraggregation. Carrier aggregation for both uplink and downlink cansupport multiple communication bands and although in many cases carrieraggregation operates on two frequency bands, the present disclosure isnot limited as such. Carrier aggregation as used herein may support two,three, four, or more communication frequency bands.

A traditional multiplexer is designed to handle particular frequencies.Generally, the multiplexer has a fixed or static design and is notcapable of handling unanticipated frequency bands. Furthermore,traditional multiplexers are designed for specific applications andcannot satisfy all potential applications because, for example, ofcompeting trade-offs in different application use cases. For example, incases where wider frequency spacing is desired, lower insertion loss isdesired for improved efficiency. However, in cases where narrowerfrequency spacing is desired, a higher isolation is desired for lowerinterference between channels. Often, reducing the insertion loss andreducing interference between channels are competing desires and it maybe challenging to maximize both factors. Thus, there are often deadzones, or unsupported frequency bands, between the supported frequencybands of traditional multiplexers. Further, the more bands supported bya multiplexer the larger the multiplexer becomes, which competes with adesire to reduce component size. In addition, each additional path addedto a multiplexer so as to support additional frequency bands may add toa loading effect on paths not in use. In other words, if the multiplexerreceives a signal of a particular frequency, the signal will beprocessed along a particular path of the multiplexer associated with thereceived signal. However, because other paths in the multiplexer thatare designed to process other frequencies generally cannot be configuredas an ideal open or short, the other paths may degrade the performanceof the particular path for the received signal. This problem isexacerbated because typically the multiplexer has a fixed design thatcannot be tuned or adjusted.

Embodiments described herein relate to a reconfigurable multiplexer thatcan support more frequency bands compared to traditional multiplexers.For example, the reconfigurable multiplexer can handle frequencies ofseveral hundred megahertz up to 10 gigahertz. Further, certainimplementations of the reconfigurable multiplexer of the presentdisclosure can reduce or eliminate frequency dead zones. In certainembodiments, the reconfigurable multiplexer includes a filter bankcapable of supporting a number of frequency bands and a bypass circuitthat enables the multiplexer to support a variety of sets offrequencies. For instance, the reconfigurable multiplexer can supportboth frequency bands with relatively narrow spacing and frequency bandswith relatively wide spacing. Frequency bands with relatively narrowspacing (e.g., a few hundred megahertz or less) may require filters thatsuffer from greater insertion loss due to design constraints. Forexample, suppose the CA signal combines band 4 and band 30. Band 4 mayhave a frequency range of 1710 MHz-2155 MHz and Band 30 may have afrequency range of 2305 MHz-2360 MHz resulting in approximately a 150MHz spacing between frequency bands. A filter designed to process the CAsignal may have an insertion loss of higher than 2 dB due to designconstraints. Alternatively, frequency bands with relatively wide spacing(e.g., spacing of more than several hundred MHz, such as 500 or 600 MHz)may be supported or processed by filters with a lower insertion loss.For example, support the CA signal combined band 3 and band 7. Band 3may have a frequency range of 1710 MHz-1880 MHz) and Band 7 may have afrequency range of 2500 MHz-2690 MHz resulting in approximately a 620MHz spacing between frequency bands. A filter designed to process the CAsignal may have an insertion loss of less than 1 dB. Further, theinclusion of the bypass circuit enables the reduction or elimination ofdead zones between supported frequencies.

In addition, in certain embodiments disclosed herein, the multiplexerincludes a number of load circuits. These load circuits enable thereduction of cross-channel interference, or the loading effect, from onecommunication channel to another. Advantageously, this reduction in theloading effect enables the multiplexer to support frequency bands thathave narrow spacing. Moreover, the re-configurability of the multiplexerand the inclusion of the bypass circuits and load circuits enable themultiplexer to support a greater number of frequency bands with a lowernumber of filters compared to a multiplexer that incorporates a separatefilter for each desired frequency band. Thus, the combination of thebypass circuit, the load circuits, and a switching network that enablesthe dynamic configurability of the multiplexer also reduces the size ofthe multiplexer while supporting more frequency bands compared to othermultiplexers that attempt to support a plurality of frequency bands withthe inclusion of additional filters.

Several embodiments are described herein with reference to one or morefrequencies. In some embodiments, a single frequency is intended.However, in other embodiments, the one or more frequencies may refer toone or more frequency bands, which may each include a range offrequencies. In some cases, the frequency may refer to a central ormid-frequency of a frequency range that constitutes a frequency band.

Example Wireless Device

FIG. 1 illustrates a block diagram of an embodiment of a wireless device11 that includes a transceiver 13. The example wireless device 11depicted in FIG. 1 can represent a multi-band and/or multi-mode devicesuch as a multi-band/multi-mode mobile phone or wireless device.Further, the wireless device 11 can support carrier aggregation for bothuplink and downlink. By way of example, the wireless device 11 canimplement the Global System for Mobile (GSM) communication standard,which is a mode of digital cellular communication that is utilized inmany parts of the world. GSM mode capable mobile phones can operate atone or more of four frequency bands: 850 MHz (approximately 824-849 MHzfor Tx, 869-894 MHz for Rx), 900 MHz (approximately 880-915 MHz for Tx,925-960 MHz for Rx), 1800 MHz (approximately 1710-1785 MHz for Tx,1805-1880 MHz for Rx), and 1900 MHz (approximately 1850-1910 MHz for Tx,1930-1990 MHz for Rx). Variations and/or regional/nationalimplementations of the GSM bands are also utilized in different parts ofthe world.

Code division multiple access (CDMA) is another standard that can beimplemented in mobile phone devices. In certain implementations, CDMAdevices can operate in one or more of 800 MHz, 900 MHz, 1800 MHz and1900 MHz bands, while certain W-CDMA and Long Term Evolution (LTE)devices can operate over, for example, as many as twenty-two, or in somecases even more, radio frequency spectrum bands.

Radio frequency (RF) modules of the present disclosure can be usedwithin a mobile device implementing the foregoing example modes and/orbands, and in other communication standards. For example, 3G, 4G, LTE,and Advanced LTE are non-limiting examples of such standards.

In certain embodiments, the wireless device 11 can include an antennaswitch module 12, a transceiver 13, one or more primary antennas 14,power amplifiers 17, a control component 18, a computer readable medium19, a processor 20, a baseband processor 40, a battery 21, one or morediversity antennas 22, and a diversity module 23. Further, although notillustrated, several of the components of the wireless device 11 may beimplemented within a front-end module (FEM). This FEM may includecomponents in a signal path that are located between the antennas 14and/or the diversity antennas 22 and a baseband processor 40 of thesignal path. For example, the FEM may include the transceiver 13, apower amplifier module that includes the power amplifiers 17, and theantenna switch module 12. In some cases, the FEM may include one or morelow noise amplifiers (LNAs).

The transceiver 13 can generate RF signals for transmission via theprimary antenna(s) 14 and/or the diversity antenna(s) 22. Furthermore,the transceiver 13 can receive incoming RF signals from the primaryantenna(s) and/or the diversity antenna(s) 22. It will be understoodthat various functionalities associated with transmitting and receivingof RF signals can be achieved by one or more components that arecollectively represented in FIG. 1 as the transceiver 13. For example, asingle component can be configured to provide both transmitting andreceiving functionalities. In another example, transmitting andreceiving functionalities can be provided by separate components.

In FIG. 1, one or more output signals from the transceiver 13 aredepicted as being provided to the antenna switch module 12 via one ormore transmission paths 15. In the example shown, different transmissionpaths 15 can represent output paths associated with different bandsand/or different power outputs. For instance, the two different pathsshown can represent paths associated with different power outputs (e.g.,low power output and high power output), and/or paths associated withdifferent bands. In some cases, such as with carrier aggregation,multiple transmit paths 15 may be operational at the same time. Thetransmit paths 15 can include one or more power amplifiers 17 to aid inboosting a RF signal having a relatively low power to a higher powersuitable for transmission. The power amplifiers 17 may be included in apower amplifier module (not shown) that includes multiple poweramplifiers for supporting different communication bands. Although FIG. 1illustrates a configuration using two transmission paths 15, thewireless device 11 can be adapted to include more or fewer transmissionpaths 15.

In FIG. 1, one or more received signals are depicted as being providedfrom the antenna switch module 12 to the transceiver 13 via one or morereceiving paths 16. In the example shown, different receiving paths 16can represent paths associated with different bands. For example, thefour example paths 16 shown can represent quad-band capability that somemobile devices are provided with. Although FIG. 1 illustrates aconfiguration using four receiving paths 16, the wireless device 11 canbe adapted to include more or fewer receiving paths 16. In some cases,such as with carrier aggregation, multiple receive paths 16 may beoperational at the same time.

To facilitate switching between receive and/or transmit paths, theantenna switch module 12 can be included and can be used to electricallyconnect a particular antenna to a selected transmit or receive path.Thus, the antenna switch module 12 can provide a number of switchingfunctionalities associated with an operation of the wireless device 11.The antenna switch module 12 can include one or more multi-throwswitches configured to provide functionalities associated with, forexample, switching between different bands, switching between differentpower modes, and switching between transmission and receiving modes, orsome combination thereof. In some cases, such as when the antenna switchmodule 12 is located between the multiplexer and antenna, the antennaswitch module can switch between different antennas (e.g., primaryantennas 14 or diversity antennas 22, or some combination thereof). Theantenna switch module 12 can also be configured to provide additionalfunctionality, including filtering and/or duplexing of signals.

FIG. 1 illustrates that, in certain embodiments, the control component18 can be provided for controlling various control functionalitiesassociated with operations of the antenna switch module 12, thediversity module 23, and/or other operating component(s). For example,the control component 18 can provide control signals to the antennaswitch module 12 and/or the diversity module 23 to control electricalconnectivity to the primary antenna(s) 14 and/or diversity antenna(s)22. Further, the control component 18 can provide control signals to thediversity module to control a sleep state of the diversity module 23, orof elements therein, such as an LDO circuit. Moreover, the controlcomponent 18 can provide control signals to the diversity module 23 tocontrol one or more bias voltages provided to elements of the diversitymodule 23. In some embodiments, the control component 18 can includevolatile memory and/or non-volatile memory, such as a read-only memory(ROM) or other computer-readable medium, which can store control statesor control instructions implemented by the control component 18. In somecases, the control component 18 can access the computer readable medium19 to determine control information for the diversity module 23 or othercomponents of the wireless device 11.

In certain embodiments, the baseband processor 40 controls operation ofcomponents involved in the receiving or transmitting of signals to andfrom a base station. For example, the baseband processor 40 may selectthe PA 17 to operate or the gain level of the selected PA 17 based oncontrol signals or configuration information received from a basestation. In some embodiments, the baseband processor 40 may include thecontrol 18.

In certain embodiments, the processor 20 can be configured to facilitateimplementation of various processes on the wireless device 11. Theprocessor 20 can be a general purpose computer, special purposecomputer, or other programmable data processing apparatus. In certainimplementations, the wireless device 11 can include a computer-readablememory 19, which can include computer program instructions that may beprovided to and executed by the processor 20.

The battery 21 can be any suitable battery for use in the wirelessdevice 11, including, for example, a lithium-ion battery. The battery 21may provide a battery voltage to one or more components of the wirelessdevice 11. In some cases, the battery voltage supplied by the battery 21does not satisfy a required voltage by one or more of the elements ofthe mobile device 21. For example, some elements may require a highervoltage, while other elements may require a lower voltage. In some suchcases, a voltage regulator (e.g., a LDO) may be used to modify a voltagesupplied to an element of the wireless device 11.

The illustrated wireless device 11 includes diversity antenna(s) 22,which can help improve the quality and reliability of a wireless link.For example, including the diversity antenna(s) 22 can reduceline-of-sight losses and/or mitigate the impacts of phase shifts, timedelays and/or distortions associated with signal interference of theprimary antenna(s) 14. In some embodiments, the wireless device 11 canswitch between use of a primary antenna 14 and a diversity antenna 23based at least in part on a quality of a received signal. This qualitymay be determined by a number of signal properties. For example, if asignal received via the primary antenna 14 is highly attenuated, orattenuated beyond a threshold, the antenna switch module 12 may switchto a diversity antenna 22.

As shown in FIG. 1, the diversity module 23 is electrically connected tothe diversity antenna(s) 22. The diversity module 23 can be used toprocess signals received and/or transmitted using the diversityantenna(s) 22. In certain configurations, the diversity module 23 can beused to provide filtering, amplification, switching, and/or otherprocessing. Further, the diversity module 23 can be used to process asignal before providing the signal to the antenna switch module 12,which can provide the signal to the transceiver 13. In some cases, thediversity module 23 can include a number of switches for switchingbetween high-band (HB) mid-band (MB), and low-band (LB) signals that maybe received by and/or transmitted over one or more of the diversityantennas 22.

Example Front-End Module

FIG. 2A illustrates a block diagram of an embodiment of a front-endmodule (FEM) 202 that includes the transceiver 13 of FIG. 1. The FEM 202also includes the antenna switch module 12. As illustrated in FIG. 2A,the FEM 202 may be positioned between an antenna 14 and a basebandprocessor 40. Although only one antenna is illustrated, the FEM 202 maybe in communication or electrical communication with multiple antennas.In some cases, the FEM 202 may communicate with both primary anddiversity antennas.

The transceiver 13 may include a power amplifier module 204 and amultiplexer 210. The power amplifier module 204 generally includes aplurality of power amplifiers (e.g., the power amplifiers 17). Furtherthe power amplifier module 204 may include a controller that controlsthe operation of the power amplifiers. This controller may activate ordeactivate one or more of the power amplifiers. Further, the poweramplifier module 204 and/or its controller may include bias circuitryfor biasing the plurality of power amplifiers and power controlcircuitry for controlling the input power provided to a plurality ofpower amplifiers.

As illustrated in FIG. 2A, the power amplifier module 204 may include anumber of output paths. Each of these output paths may be associatedwith a different power amplifier of the power amplifier module 204.Further, each of the output paths may be associated with a differentcommunication band or transmit band. For example, as illustrated in FIG.2A, the power amplifier module 204 has six outputs, which may correspondto six different communication bands. At least some of the sixcommunication bands may be aggregated together as part of carrieraggregation (CA) communication. These six paths may be provided to themultiplexer 210, which can provide an output from one or more of thepower amplifiers to the antenna switch module 12. In some cases, theoutput of the multiplexer 210 is provided directly to an antenna 14 andis not provided to the antenna switch module 12.

For devices that support carrier aggregation, the multiplexer may belocated between the power amplifier module (PAM) 204 and the antennaswitch module 12 as illustrated in FIG. 2A. Alternatively, or inaddition, as illustrated in FIG. 2B, the multiplexer 210 may be locatedbetween the antenna switch module 12 and the antenna 14. The multiplexer210 may support carrier aggregation (CA) downlink communication and CAuplink (CAUL) communication.

The baseband processor 40 may control the configuration of themultiplexer 210 and/or the antenna switch module 12. The basebandprocessor 210 may provide a control signal to the multiplexer 210 toselect one or more communication paths. Further, the baseband processor210 may provide a control signal to configure elements of themultiplexer 210, as will be described in more detail below, based onselection of one or more communication bands by a base station. Thecommunication bands may be identified during a handshake process withthe base station. Alternatively, or in addition, the base station mayidentify one or more communication bands during communication with thewireless device that includes the FEM 202.

In addition, the baseband processor may provide a control signal to theantenna switch module 12 to select a transmit path to transmit a signal,or a receive path to receive a signal. Further, the selection of thepaths may be based on a selection of a communication band identified bya base station for transmitting or receiving signals from the wirelessdevice 11.

The baseband processor 40 includes a call processor 212 and a modem 214.Further, in some cases, the baseband processor 40 includes a lookuptable 218. The modem can perform modulation and demodulation of data andvoice for transmission. The call processor 214 may control the timing ofcommunication with the base station. Further, the call processor 214 maycontrol the switches of the antenna switch module 208. In someembodiments, the call processor 214 may also control the poweramplifiers of the power amplifier module 202. In addition, as isdescribed in more detail below, the call processor 212 may control theswitches of the multiplexer 210. The call processor 212 may determinethe configuration of the multiplexer 210 based on information stored inthe lookup table 216. This lookup table 216 may be stored in anon-volatile memory, such as a ROM. Further, the call processor 212 mayaccess the information stored in the lookup table 216 based onconfiguration information provided by the base station.

FIG. 2B illustrates a block diagram of an alternative or additionalarrangement of a front-end module 202 that includes the transceiver ofFIG. 1. As illustrated in FIG. 2B, the multiplexer 210 may be locatedbetween the antenna 14 and the antenna switch module 12. Further, thetransceiver may include one or more low noise amplifier (LNA) receivers250. The LNA receivers 250 may receive and process received signals fromthe antenna 14 and is typically located within the receive path 16 ofthe wireless device 11. In contrast, the power amplifier module 204 isgenerally in the transmit path of the wireless device 11.

In certain embodiments, a multiplexer 210 may be located both betweenthe antenna and the antenna switch module 12 and between the poweramplifier module 204 and the antenna switch module 12. Advantageously,in certain embodiments, the multiplexer 210 between the antenna switchmodule 12 and the power amplifier module 204 may enable the support oftransmission via multiple antennas.

Example Multiplexer

FIG. 3 illustrates a block diagram of an embodiment of the multiplexer210 of FIG. 2A. As illustrated, the multiplexer 210 includes a bypasscircuit 310 and a filter bank 320. The bypass circuit 310 and filterbank 320 may connect to port 302. This port 302 may be from an antenna14, and the signal at the port 302 may be a carrier aggregated signalformed from multiple communication bands. Generally, the port 302 may beboth an input port and an output port. For example, when the wirelessdevice 11 is receiving a signal, the antenna may provide the receivedsignal to the multiplexer 210 via the port 302 for processing by themultiplexer 210. If on the other hand the wireless device 11 istransmitting a signal, the port 302 may serve as an output port thatprovides the signal, which may be a CA signal, to an antenna of thewireless device 11 for transmission.

As will be described in more detail below, the configuration of thebypass circuit 310 and the filter bank 320 may be determined based onthe communication band or bands being utilized by the wireless device11. Further, in some cases, only one of the bypass circuit 310 and thefilter bank 320 may be operational based on the selected communicationbands.

Further, the multiplexer 210 may include a bypass load circuit 314 andone or more filter load circuits 324A, 324B, and 324C (which maycollectively be referred to as “filter load circuits 324”). Althoughonly one bypass load circuit 314 is illustrated, in some embodiments,the multiplexer 210 may include multiple bypass load circuits 314. Thebypass load circuit 314 and the filter load circuits 324 can be used toreduce, minimize, or eliminate the insertion loss that can occur withthe operation of multiple communication paths during carrieraggregation.

The multiplexer 210 can include a switch 312 that switches between thebypass load circuit 314 and the port 304A. Further, in some cases, thebypass circuit 310 may be deactivated. In such cases, the switch 312 maybe placed in an open position. Similarly, one or more switches mayconnect one or more outputs of the filter bank 320 to correspondingfilter load circuits or to corresponding output ports of the multiplexer210. For instance, as illustrated in FIG. 3, one output port of thefilter bank 320 may be in communication with a switch 322A. The switch322A may direct the output of the filter bank 322 either to a port 304Bof the multiplexer 210 or to a filter load circuit 324A. Further, if acorresponding filter of the filter bank 320 is deactivated, the switch322A may be placed in an open position. Another output port of thefilter bank 320 may be in communication with a switch 322B. The switch322B may direct the output of the filter bank 322 either to a port 304Cor to one of the filter loads 324B and 324C. The selection of the filterload circuits 324B or 324C may be based on the operational communicationbands. As previously mentioned, the load circuits, including the filterload circuits 324 and the bypass load circuits 314, may be selected toreduce insertion loss for the selected communication bands. Further, ifa corresponding filter of the filter bank 320 is deactivated, the switch322B may be placed in an open position.

As with the port 302, the ports 304A, 304B, and 304C (which maycollectively be referred to as ports 304) can be both input ports andoutput ports. For example, if the wireless device 11 is receiving asignal, the ports 304 may serve as output ports that provide the signal,or portions of the signal associated with particular frequency bands, tothe LNA receivers 250. On the other hand, if the wireless device 11 istransmitting a signal, the ports 304 may serve as input ports thatreceive one or more components of the signal associated with one or morefrequency bands. The signal and/or CA signal may be output by the port302 for transmission by the antenna.

Second Example Multiplexer

FIG. 4A illustrates a block diagram of another embodiment of themultiplexer 210 of FIG. 2A. As with the multiplexer 210 of FIG. 3, themultiplexer 210 of FIG. 4A includes an input port 302 that directs asignal to the bypass circuit 310 and the filter bank 320.

The filter bank 320 includes a number of filter circuits. The filtercircuits can include a high pass filter 420, a low pass filter 424, anda number of band pass filters 422A-422N (which are collectively referredto herein as “band pass filters 422”). The designation of high frequencybands that may be processed by the high pass filter 420, mid frequencybands that may be processed by the band pass filters 422, and lowfrequency bands that may be processed by the low pass filter 424 mayvary based on applications or manufacturer specification, and thisdisclosure is not limited by a specific designation of what constituteslow, mid, or high frequency. In certain embodiments, the low frequencybands may include communication bands below 960 MHz, such as between 450MHz and 960 MHz. Further, the mid frequency band may include frequenciesbetween 1400 MHz and 2200 MHz. Moreover, the high frequency band may bebetween 2300 MHz and 6000 MHz. Although only one high pass filter 420 isillustrated and one low pass filter 424 is illustrated, the presentdisclosure is not limited as such. The filter bank 320 can include anynumber of high pass and/or low pass filters. Further, in some cases, thefilter bank 320 may omit a high pass filter 420 or a low pass filter424. Moreover, although a plurality of band pass filters 422 areillustrated, the filter bank may include zero, one, or any other numberof band pass filters 422. Each band pass filter 422 may be configured toallow a different frequency or set of frequencies to be provided to asubsequent element while filtering out other frequencies.

The bypass circuit 310 may include one or more bypass circuits. In theillustrated example, two bypass circuits 410A and 410B are depicted.However, the bypass circuit 310 may include more or fewer bypasscircuits. The bypass circuits 410A and 410B enable the use of CA withfrequency bands that are not supported by traditional multiplexerdesigns. Further, a single bypass circuit may be active while anyadditional included bypass circuits may be deactivated (e.g., providedwith an open load) to enable non-CA communication. A variety ofimplementations are possible for the bypass circuits 410A and 410B. Forexample, the bypass circuits 410A and 410B may be a phase shift networkas illustrated in FIG. 4. As additional examples, the bypass circuits410A and 410B may be transmission lines, lumped element LC phase shiftnetworks, reflection-type phase shift networks, LC networks, and thelike. In some embodiments, the bypass circuits 410A and 410B may providedirect connections between the input port 302 and the switches 406A and406B, respectively. Further, in some cases, the bypass circuits 410A and410B may be different types of circuits. For example, the bypass circuit410A may be a transmission line and the bypass circuit 410B may be aphase shift network.

As with the example of FIG. 3, the output of bypass circuits 410A and410B and the output of the high pass filter 420, the band pass filters422, and the low pass filter 424 may be provided to a set of switches406A-406F, respectively (which may collectively be referred to asswitches 406). Each of the switches 406A-406F may switch between arespective output port 404A-404F (collectively referred to herein asoutput ports 404) and a respective set of load circuits 430A-430F(collectively referred to herein as load circuits 430). Further, in somecases, at least one of the switches 406 is capable of being configuredin an open position such that neither the respective output port nor theassociated load circuit is in electrical communication with the switch.

The set of load circuits 430 may each include one or more load circuitsthat are configured to provide a different terminal load to the bypasscircuits 410A, 410B or the filter circuits 420, 422, or 424. Forexample, the bypass circuit 410A may be electrically connected to theoutput port 404A, Load1 of the set of load circuits 430A, or Load2 ofthe set of load circuits 430A. The bandpass processor 40 may determinewhether to connect the bypass circuit 410A, via the switch 406A, to theoutput port 404A, Load1 of the load circuits 430A, or Load2 of the loadcircuits 430A based on frequency band or bands identified forcommunication by, for example, a base station. By including multipleload circuits in each set of load circuits 430, the insertion loss canbe reduced by selecting the optimal load circuit from the available loadcircuits based on the frequency of a signal received by the multiplexer210 in a single frequency band case or the frequencies received ofsignals used in a CA case. The optimal load circuit for differentfrequencies and/or use cases may be determined by simulation orload-pull measurement. In the case of a high band/low band (HB/LB) CAsignal, the mid band (MB) or band pass filters and the bypass paths maybe unused. By doing load-pull measurements of the unused ports andchecking the insertion loss of the HB and LB filter paths, the optimalloads can be found for each path in the multiplexer. In some use cases,the optimal loads may be shorts or series circuits, such as 50 Ohmcapacitors or inductors in series. Thus, the performance of themultiplexer 210 can be tuned based on the received signals. For example,in the case of a CA signal that includes a high frequency to be filteredby the high pass filter 420 and a low frequency to be filtered by thelow pass filter 424, one or more of the bypass circuits 410A, 410B maybe connected via the switches 406A, 406B, respectively, to load circuitsselected to reduce or minimize the insertion loss along the signal pathsassociated with the high pass filter 420 and the low pass filter 424.

The load circuits 430 are configured to reduce the insertion loss inselected communication paths that are selected based on the desiredcommunication frequency bands. For example, if a wireless device isconfigured to use CA combining both a high and a low frequency, the highpass filter 420 may be electrically connected to the output port 404Cand the low pass filter 424 may be electrically connected to the outputport 404F. Further, to reduce any insertion loss from the selectedcommunication paths, one or more of the bypass circuits 410A and 410Bmay be electrically connected, respectively, to one of the load circuitsfrom the set of load circuits 430A and 430B. In some cases, the filtersand bypass paths are physically connected at one node. The isolationbetween two paths is typically not infinite. Therefore, the load circuitconnected after the filter bank or the bypass circuits may cause mutualinterference. Generally, this interference will cause the signal todeteriorate and cause insertion loss along a path within themultiplexer. However, the inclusion of a load circuit can help reducethe interference and the insertion loss.

Moreover, in some cases, the load circuits 430 can reduce the loadingeffect of one communication path in the multiplexer 210 on anothercommunication path within the multiplexer 210. The multiplexer 210 canbe tuned or reconfigured to reduce the loading effect by connecting oneor more paths leading from the bypass circuits 310 and/or from thefilter bank 320 to particular load circuits based on the frequency orfrequencies of the signal or signals received by the multiplexer 210.

The load circuits may include LC circuits. In some cases, the one ormore of the load circuits may be tunable providing additionalflexibility to the multiplexer 210 and enabling a further reduction inboth the loading effect and insertion loss. For example, the capacitorsof the LC load circuits may be switched capacitors enabling theconfiguration of individual load circuits of the multiplexer 210. Insome cases, the load circuits may include short or open circuits.

FIG. 4B illustrates some example circuits that may be used as loadcircuits for the multiplexer 210 of FIG. 4A. As illustrated in FIG. 4B,at least some of the load circuits may include a high Q resonator 452(e.g., a resonator with a relatively low rate of energy loss compared tothe stored energy). Alternatively, or in addition, at least some of theload circuits may include a capacitor load circuit 454, which mayinclude one or more capacitors in series, an inductor load circuit 456,which may include one or more inductors in series, or a resistor loadcircuit 458, which may include one or more resistors in series. Further,in some cases, at least some of the load circuits may include an LCshort circuit 460, which may include a set of capacitors in series witha set of inductors. Moreover, at least some of the load circuits mayinclude an LC open circuit 462, which may include a set of capacitors inparallel with a set of inductors. It should be understood that the loadcircuits of FIG. 4B are non-limiting examples of load circuits. Othertypes of load circuits may be used in certain embodiments of the presentdisclosure.

Returning to FIG. 4A, the output ports 404 may be connected to one ormore antennas, such as the primary antennas 14 and/or the diversityantennas 22. In some cases, a plurality of output ports may be inelectrical communication with the same antenna. In some implementations,the output ports 404 may connect to one or more elements between themultiplexer 210 and the antennas.

As previously described with respect to FIG. 3, the ports may be dualdirectional ports. Thus, the port 302 and the ports 404 may serve asboth input ports and output ports based on whether the multiplexer isprocessing a receive signal or a transmit signal.

Example Dynamic Multiplexer Configuration Process

FIG. 5 presents a flowchart of an embodiment of a dynamic multiplexerconfiguration process 500. The process 500 can be implemented by anysystem that can configure a multiplexer based, at least in part, on thefrequency band or bands being used to communicate with another device,such as a base station. For example, the process 500 may be performed bya baseband processor 40, a call processor 212, a lookup table 216, acontrol 18, or a processor 20, to name a few. Although one or moresystems may implement the process 500, in whole or in part, to simplifydiscussion, the process 500 will be described with respect to particularsystems.

The process 500 begins at the block 502 where, for example, the basebandprocessor 40 receives a control signal from a base station identifyingone or more communication frequencies. In some cases, the control signalis received by another element of a wireless device and is provided tothe baseband processor 40. At decision block 504, the baseband processor40 determines whether the control signal identifies a single frequency.In some cases, the baseband processor 40 determines whether the controlsignal identifies a single frequency band, which may be of a particularbandwidth.

If the control signal does identify a single frequency or frequencyband, the wireless device 11 is communicating over a single frequency orfrequency band in carrier aggregation is not being implemented orutilized. Thus, if it is determined at the decision block 504 that thecontrol signal identifies a single frequency or frequency band, thebaseband processor 40 deactivates the filter bank 320 at block 506.Deactivating the filter bank 320 may include ceasing to provide or notproviding a voltage or power to the filter bank 320. Alternatively, orin addition, deactivating the filter bank 320 may include opening theswitches 406C-406F. In some cases, deactivating the filter bank 320 mayinclude connecting each of the filters of the filter bank 322 ground.

At block 508, the baseband processor 40 connects a bypass path (e.g.,the bypass path associated with the bypass circuit for today) to anoutput path, which is in electrical communication with the output port404A. Further, the baseband processor 40 disconnects the remainingbypass paths at block 510. Thus, with reference to the example of FIG.4, the bypass path associated with the bypass circuit 410B isdisconnected. Disconnecting the bypass path associated with the bypasscircuit 410B may include deactivating the bypass circuit 410B by, forexample, ceasing to provide or not providing a voltage or power to thebypass circuit 410B. Further, disconnecting the bypass path associatedwith the bypass circuit 410B may include opening the switch 406B. Insome cases, disconnecting the bypass path may include connecting thebypass circuit 410B to ground.

It is determined at the decision block 504 that the control signalidentifies multiple frequencies were multiple frequency bands, thewireless device 11 is communicating using carrier aggregation. At block512, the baseband processor 40 configures the filter bank 320 based onthe identified frequencies. Configuring the filter bank 320 may includeaccessing a lookup table 216 to determine the switch configurations forthe switches 406C-406F based on the identified frequencies.

At the decision block 514, the baseband processor 40 determines whetherthe control signal identifies common CA bands. These common CA bandsinclude frequency bands that are typically used in carrier aggregationcommunication. Often, the combination of frequency bands will be acombination of a low-band with a mid-band, a mid-band with a high-band,or a low-band with a mid-band with a high-band. However, othercombinations may be possible. In some cases, the common CA bands mayinclude a combination of two or more of the following frequency bands:Band 3 (1710-1880 MHz); Band 7 (2550-2690 MHz); Band 49 (1880-1920 MHz);Band 41 (2496-2690 MHz); and Band 5 (824-894 MHz). Typically, the commonCA bands include frequency bands with larger spacing, such as 150 MHz ormore. In some cases, the common CA bands may have spacing of 300 MHz ormore. Bands that are directly adjacent or that have overlappingfrequency are typically not defined as CA combinations. Further, thecommon CA bands may have an isolation requirement of approximately 20 dBor more. The filter bank may be optimized to process the common CA bandfrequencies, and thus, usually, it is unnecessary for unused paths to beterminated with a particular load circuit. Generally, the common CAbands are communication bands that have been identified for carrieraggregation by one or more wireless communications standard-settingbodies or entities. Further, the common CA bands are typically separatedby enough frequencies that a special filter is not required and a filterwith low insertion loss can be used. If it is determined that thecontrol signal identifies common CA frequency bands, the basebandprocessor 40 disconnects the bypass paths at the block 516.Disconnecting the bypass paths can include one or more of theembodiments described with respect to the block 510.

If it is determined at the decision block 514 that the control signalidentifies one or more frequency bands that are not typically used incarrier aggregation, the baseband processor 40 determines at thedecision block 518 whether the control signal identifies one or morespecial carrier aggregation frequency bands. The special CA bands may bedistinguished from the common CA bands based on how frequently thespecial CA bands are used compared to the common CA bands. The specialCA bands may be used less frequently because of the expense, and size ofthe filters and multiplexers to support the frequency bands. Further,such filters and multiplexers may be less efficient due to insertionloss. Moreover, designing the filters and multiplexers can bechallenging. However, the embodiments disclosed provide a reconfigurablemultiplexer that enables support for special CA bands that areunsupported by traditional multiplexers or are supported moreefficiently compared to traditional multiplexers.

The special CA bands can include frequencies that are not typically usedin carrier aggregation because, for example, the spacing between thebands is relatively narrow. For example, the spacing between the bandsmay be 150 Mhz, 100, MHz, or less. For example, the special CA bands mayinclude a CA signal that combines Band 4 and Band 30, which has aspacing of approximately 150 MHz. In certain embodiments, although thespacing for the special CA bands may vary, it will be less than thespacing for the common CA bands. Typically, the filter bank is notoptimized to handle these bands together and thus, the inclusion ofapplication specific load terminations or load circuits for the unusedpaths can be used to enable the multiplexer to process the special CAbands. Further the special CA bands may include frequencies that areoften found within the dead zones or zones not supported by traditionalmultiplexers. In some cases, the special CA bands include frequenciesthat can be challenging to filter and often require filters with highertolerances because, for example, the frequencies are relatively closetogether and consequently may require a sharp filter to separate.Including these higher tolerance filters can result in larger and moreexpensive multiplexers. Advantageously, in certain embodiments, theinclusion of the bypass circuit 310 enables the multiplexer 310 tosupport the special CA bands. Further, in certain embodiments, thebypass circuit 310 enables the multiplexer 310 to support the special CAbands without increasing the size or complexity of the filter bank 320.

If it is determined at the decision block 518 that the control signalidentifies one or more special CA frequency bands, the basebandprocessor 40 connects one or more bypass paths to a particular loadcircuit (e.g., Load1 from the set of load circuits 430A) based on theidentified frequencies at block 520. In some cases, the basebandprocessor 40 may access a lookup table 216 to determine the particularloads to terminate the bypass circuits 410A and/or 410B with based onthe identified frequencies. For instance, the baseband processor 40 maydetermine that the bypass circuit 410B is to be electrically connectedwith Load2 of the load circuits 430B based on the identifiedfrequencies. By connecting the bypass circuit 410B to the Load2, aloading effect on communication paths leading from the filter bank 320may be reduced enabling filters of the filter bank 322 provide improvedfiltering or filtering with a sharper shape compared to multiplexersthat do not include the bypass circuit 310. At block 522, the basebandprocessor 40 disconnects remaining bypass paths. The block 522 caninclude one or more of the embodiments described with respect to theblock 510. In some cases, the block 522 may be optional or omitted. Forexample, in some cases each of the bypass circuits 310 may be configuredto electrically connect to a load circuit. Thus, in such cases, none ofthe bypass paths may be disconnected.

If it is determined at the decision block 518 that the control signaldoes not identify special CA frequency bands, it is determined that theidentified frequencies are unlicensed frequency bands or licenseassisted access frequency bands (e.g., LTE-U or LTE-LAA bands). Thesefrequencies are typically between 3.4 and 6 GHz. In some embodiments,the baseband processor 40 confirms whether the identified frequenciesare LTE-U or LTE-LAA frequencies. If it is determined that theidentified frequencies are not LTE-U or LTE-LAA frequencies, thewireless device 11 may output a signal to, for example, a base stationindicating that identified frequencies are unsupported.

If it is determined that the identified frequencies are LTE-U or LTE-LAAfrequencies, the baseband processor 40 connects a bypass path to anoutput path or an output port at block 524. For example, the basebandprocessor 40 may configure the switch 406A to connect the bypass circuit410A to the output port 404A. At block 526, the baseband processor 40connects the remaining bypass paths to load circuits selected based onthe identified frequencies. In certain embodiments, the bypass pathshave lower insertion loss compared to paths that include a filter fromthe filter bank 320. Thus, by turning on or connecting a bypass path toan output port at the block 524, a wider frequency spacing can besupported compared to multiplexers that do not incorporate the bypasscircuits 310. Advantageously, in certain embodiments, the ability tosupport the wider frequency spacing enables the support of LTE-U orLTE-LAA bands that are not supported by some other multiplexers.

Second Example Dynamic Multiplexer Configuration Process

FIG. 6 presents a flowchart of an embodiment of a second dynamicmultiplexer configuration process 600. As with the process 500, theprocess 600 can be implemented by any system that can configure amultiplexer based, at least in part, on the frequency band or bandsbeing used to communicate with another device, such as a base station.For example, the process 600 may be performed by a baseband processor40, a call processor 212, a lookup table 216, a control 18, or aprocessor 20, to name a few. Although one or more systems may implementthe process 600, in whole or in part, to simplify discussion, theprocess 600 will be described with respect to particular systems.Further, a number of the operations that may be performed as part of theprocess 600 are similar to the operations that may be performed as partof the process 500 and share the same reference numerals. Thus, tosimplify discussion, descriptions of blocks of FIG. 6 that share thesame reference numerals with blocks of FIG. 5 are not repeated below.

As with the process 500, the process 600 begins with embodiments of theoperations of block 502, which may then proceed to the operations ofdecision block 504. Further, if it is determined at the decision block504 that the control signal identifies a plurality of frequencies, theprocess 600 proceeds to the block 512 where the process 600 continues toproceed similarly to the process 500 described with respect to FIG. 5.

However, if it is determined at the decision block 504 that the controlsignal identifies a single frequency, or single frequency band, thebaseband processor 40 determines whether the frequency is supported bythe filter bank 320 at decision block 602. Determining whether thefrequency is supported by the filter bank 320 may include determiningwhether the filter bank 320 includes a filter designed to pass thefrequency while filtering out or removing other frequencies and/orundesired harmonics of the frequency. For instance, if the frequency is2620 MHz, which is the central frequency of Band 7, the basebandprocessor 40 may determine whether the filter bank 320 includes a filterconfigured to pass Band 7 signals while rejecting non-Band 7 signals.This determination may be made by accessing a table of supportedfrequency bands from, for example, the lookup table 216.

If it is determined at the block 602 that the frequency is not supportedby the filter bank 320, the process 600 proceeds to the block 506 wherethe filter bank is deactivated. The remainder of the process 600subsequent to the block 506 is similar to the process 500 and thediscussion is not repeated.

On the other hand, if it is determined at the block 602 that thefrequency is supported by the filter bank 320, the process 600 proceedsto the block 604. At the block 604, the baseband processor 40 providesone or more control signals to the multiplexer 210 that cause the filterof the filter bank 320 that corresponds to the frequency to be placed inelectrical connection with the corresponding output port. In otherwords, in certain embodiments, the filter bank 320 is configured toenable the signal to pass through the filter corresponding to thefrequency band of the signal. At block 606, the remaining paths withinthe multiplexer 210 are disconnected. Thus, the switches correspondingto the non-selected filters may be opened. Further, the switchescorresponding to the bypass paths are opened. Advantageously, in certainembodiments, by connecting the single frequency or signal frequency bandto a filter path, spurious signals, noise, and undesired harmonics maybe removed from the signal. However, in cases where the filter bank 320does not include a corresponding filter, bypass circuits can enable themultiplexer 210 to support communication of the signal. In embodimentswhere it is desired to prevent communication via a particular frequency,the multiplexer 210 can be configured to open the switches and/orconnect the switches to terminal loads in the multiplexer 210 to preventthe signal from being passes to the antenna and/or to the receiver LNAs.

Triplexers

In certain embodiments, the multiplexer 210 of the front-end module 202can be replaced with a triplexer. Advantageously, in certainembodiments, the design of a triplexer can be easier than certainmultiplexer designs, thereby resulting in reduced resource usage andless strict tolerances compared to certain multiplexer designs. Forexample, as will be discussed in more detail with respect to FIGS.7A-7E, a triplexer can be designed with cascading diplexers thateliminate the need for a bandpass filter. In certain cases, a band passfilter may be more difficult to design compared to a low pass filter ora high pass filter because, for example, the band pass filter isconfigured to prevent frequencies both below a first threshold andfrequencies above a second threshold. In contrast, a low pass filter isconfigured to prevent frequencies above a single threshold andsimilarly, the high pass filter is configured to prevent frequenciesbelow a single threshold.

As band pass filters can be more challenging to design compared to lowpass and/or high pass filters, by eliminating the need for a band passfilter, the triplexer can be simplified compared to certain multiplexerdesigns resulting in the expenditure of less resources compared to thatutilized in certain multiplexer designs. Consequently, in certainembodiments, triplexers may be easier and cheaper to produce thancertain multiplexers because, for example, the triplexers may requireless strict tolerances than certain multiplexers. Further, in certainembodiments, the triplexer may have a smaller footprint due, forexample, to the lower tolerances required by the filters of thetriplexer compared to that of certain multiplexers that may include anumber of band pass filters. For example, the filters of the triplexermay be designed with fewer capacitors and/or smaller inductors comparedto a multiplexer that may include a band pass filter.

Example Triplexer Design

FIG. 7A illustrates a block diagram of an embodiment of a triplexer 710that may serve as an alternative to the multiplexer 210 of FIG. 2A andFIG. 2B, and as further illustrated in FIG. 3 and FIG. 4. The triplexer710 may receive an input signal via the input port 302. This inputsignal may be a CA signal comprising multiple frequency bands. Further,this input signal may be provided to a filter bank 720A, which can splitthe CA signal into its constituent frequency bands. The output of thefilter bank 720A may be provided to a switch bank 406, which may in turnprovide the one or more signals to a set of one or more loads, or a loadbank 430. Alternatively, or in addition, the one or more signals may beprovided to a set of one or more output ports 404. The input port 302,the switch bank 406, the load bank 430, and the output ports 404 mayinclude one or more of the embodiments previously described with respectto the multiplexer 210.

The filter bank 720A may include a number of diplexers arranged in acascade design, which may also be referred to as a daisy chain. In otherwords, in certain embodiments, a set of one or more filters within thefilter bank 720A may be connected in series with another set of one ormore filters in the filter bank 720A. In the example of FIG. 7A, thefilters of the filter bank 720A are arranged in two tiers, levels, orstages. Although FIG. 7A only illustrates two tiers of filters, thepresent disclosure is not limited as such and any number of tiers orsets of filters may be connected in a cascade design as part of thefilter bank 720A.

The first tier or stage of filters in the illustrated example of FIG. 7Aincludes a low pass filter 722 and a high pass filter 724. Thesefilters, and the other illustrated filters of the filer bank 720A, maybe diplexers. However, the present disclosure is not limited as such,and it should be understood that other types of circuits may be used toimplement the filters of the filter bank 720A.

In one non-limiting example, the low frequency band (“LB”) may includefrequencies below 960 MHz and the mid (“MB”) and/or high frequency band(“HB”) may include frequencies above 1400 MHz. Thus, the low pass filter722 may pass frequencies below 960 MHz and block frequencies at or above960 MHz and the high pass filter 724 may pass frequencies above 1400 MHzand block frequencies below or at 1400 MHZ. In this non-limitingexample, frequencies between 960 MHz and 1400 MHz may be blocked,filtered, or not processed by the triplexer 720A. However, it should beunderstood that, in certain implementations, different filters may beused to accommodate different frequency bands. For example, in asatellite television receiver, the filters may be configured to passfrequencies between 950 MHz and 1450 MHz.

The second tier or stage of filters in the illustrated example of FIG.7A includes a second low pass filter 726 and a second high pass filter728. As stated above, these filters may be, but are not limited to,diplexers. In one non-limiting example, the mid frequency band mayinclude frequencies between 1400 MHz and 2200 MHz, and the highfrequency band may include frequencies above 2300 MHz. Thus, the lowpass filter 726 may pass frequencies below 2200 MHz and blockfrequencies at or above 2200 MHz. As frequencies below 1400 MHz areblocked by the high pass filter 724, the resultant signal output by thelow pass filter 726 will be between 1400 and 2200 MHZ.

The high pass filter 728 may pass frequencies above 2300 MHz and blockfrequencies below or at 2300 MHZ. In this non-limiting example,frequencies between 2200 MHz and 2300 MHz may be blocked, filtered, ornot processed by the triplexer 720A. However, it should be understoodthat, in certain implementations, different filters may be used toaccommodate different frequency bands.

In addition to the above-described filters, the filter bank 720A mayinclude a bypass circuit 730. In certain embodiments, the bypass circuit730 may include one or more of the embodiments previously described withrespect to the set of bypass circuits 310 and/or the circuits 410A, 410Bthat may be included as part of the bypass circuit 310. Further, thefilter bank 720A may include a switch 732 that may be used toelectrically connect or disconnect the bypass circuit 730 from the nodebetween the high pass filter 724 and the second tier or stage offilters. In certain embodiments, the switch 732 may be a transistor. Incertain embodiments, the switch 732 is optional and may, in someimplementations, be omitted. In some cases, the omission of the switch732 may result in higher insertion loss when operating in the bypassmode.

During operation, the switch 732 may be opened when a MB/HB CA signal isreceived by the wireless device that includes the triplexer 710. Theoperation of the switch may be controlled by, for example, the basebandprocessor 40 or the call processor 212 in response to a control signalreceived from a base station. Further, in some cases, the bypass circuit730 may be deactivated by, for example, disconnecting a power supplyfrom the bypass circuit 730.

When the wireless device that includes the triplexer 710 is operating ina non-CA mode, the switch 732 may be closed enabling signal frequenciesabove 1400 MHz to be provided to the bypass circuit 730 instead of thefilters 726, 728. As a result, the triplexer 710 may have lower losscompared to designs that do not include the bypass circuit 730.

In certain embodiments, the bypass circuits 310 and/or 730 may include anon-linear device. In some cases, it is not desirable to connect thenon-linear device directly to the antenna. For example, suppose that aCA signal aggregates a band 3 and a band 8 signal. In such a case, thesecond harmonic of the band 8 signal could pass through the band 3 pathaffecting the processing of the band 3 signal. In such an example, itwould be desirable to use a low pass filter to reduce the interferenceof the band 8 second harmonic on the band 3 signal. Further, continuingthe previous example, a low pass filter may be used in the band 3 pathto reject the fundamental signal of band 8. The low pass filter may bedesired because the band 8 fundamental signal may generate unacceptableharmonics at a non-linear device in the band 3 signal path.Advantageously, by using a cascade design, the high pass filter 724 maybe included in the signal path of the bypass circuit 730 preventing thehigh level signal components of a low band signal from generatingharmonics on a non-linear device, such as switch 732.

Additional Example Triplexer Designs

FIGS. 7B-7E present a number of alternative triplexer designs. Each ofthe triplexer designs may include some or all of the embodimentspreviously described with respect to FIG. 7A. Further, reference numberfrom FIG. 7A are re-used to indicate correspondence between referencedelements.

FIG. 7B illustrates a block diagram of a second embodiment of thetriplexer 710 of FIG. 7A. The triplexer 710 of FIG. 7B includes a filterbank 720B that is a modified version of the filter bank 720A. The filterbank 720B includes an additional switch 734 located between the highpass filter 724 of the first filter stage and the second filter stage.The switch 734 enables the second filter stage to be disconnected whenthe filter bank 720B is operating in a bypass mode. Advantageously, incertain embodiments, by including the switch 734, improved isolation canbe achieved and the loading effect on the bypass path can be reduced.

FIG. 7C illustrates a block diagram of a third embodiment of thetriplexer 710 of FIG. 7A. The triplexer 710 of FIG. 7C includes a filterbank 720C that is a modified version of the filter bank 720A. The filterbank 720C separates the bypass circuit into two separate bypass circuits730 and 742. The bypass circuit 730 can be optimized for use with thehigh band frequency and the bypass circuit 742 can be optimized for usewith the mid band frequency. Further, the filter bank 720C can includeswitches 738 and 740 positioned after the low pass filter 726 and thehigh pass filter 728, respectively, in the high band and mid band signalpaths. Advantageously, in certain embodiments, isolation can be improvedand the loading effect reduced by the addition of the additionalswitches in the mid band and high band signal paths. Further, althoughin some cases, the filter bank 720C may be more complex compared to someof the other embodiments disclosed herein, the filter bank 720C iseasier to optimize for various use cases because, for example, of theseparate bypass circuits and improved isolation capabilities of thefilter bank 720C.

When operating in the MB/HB CA case, the bypass circuits 730 and 742 maybe disabled. Further, the switches 732 and 736 may be opened and theMB/HB CA signal may be processed by the second stage filters 726 and728. However, when operating in a non-CA case, or when the CA is one ofthe HB or MB in combination with the LB, the MB or HB signal may beprocessed by the respective bypass circuit 742 or 730. For example, inthe CA case that combines a MB and LB signal, the MB signal may beprovided to the bypass 742 with the switches 734, 738 and 732 open andthe switch 736 closed. As another example, in the CA case that combinesa HB and LB signal, the HB signal may be provided to the bypass 730 withthe switches 728, 734 and 736 open and the switch 732 closed.

FIG. 7D illustrates a block diagram of a fourth embodiment of thetriplexer 710 of FIG. 7A. The triplexer 710 of FIG. 7D includes a filterbank 720D that is a modified version of the filter bank 720A. The filterbank 720D is a variant of the filter bank 720C that includes a singlebypass circuit 742 that may be used for either mid band or high bandfrequencies. The filter bank includes a switch 746 that can be used tolet HB and MB share one bypass in non-CA mode or any MB/LB, HB/LB CAmode.

FIG. 7E illustrates a block diagram of a fifth embodiment of thetriplexer 710 of FIG. 7A. The triplexer 710 of FIG. 7E includes a singlestage filter bank 720E. Further, the triplexer 710 includes a pluralityof input ports 750A, 750B, and 750C. Although three input ports areillustrated, in certain embodiments, the filter bank 720E may bemodified to receive any other number of inputs. For example, thetriplexer 710 of FIG. 7E could have two or four input ports.Advantageously, in certain embodiments, the use of separate input portscan reduce the loading effect and improve isolation of the signal paths.Further, the number of filters may be reduced. For example, the filterbank 720E eliminates one high pass filter compared to the filter bank720A. Further, the HB signal path associated with the input port 750Acan be associated with the bypass circuit 730, which can be optimizedfor the high frequency signal (e.g., signals above 2300 MHZ). Similarlythe MB signal path associated with the input port 750B can be associatedwith the bypass circuit 742, which can be optimized for the mid bandfrequency signal (e.g., signals between 960 and 2200 MHZ). It should beunderstood that the frequency of the low band, the mid band, and thehigh band signals may be application specific and may vary for differentimplementations. Thus, for example, in one non-limiting alternativeexample, the high band frequency may be frequencies above 5000 MHz andthe mid band frequency may be between 2500 and 5000 MHZ and the low bandfrequency may be below 2500 MHZ.

Moreover, the signal paths can include a number of switches to improveisolation. For example, when using the bypass circuit 730, the switches740 and 746 can be opened and the switch 732 can be closed. Similarly,when using the bypass circuit 744, the switches 738 and 744 can beopened and the switch 736 can be closed. When the bypass circuits arenot being used, the switch leading to the respective bypass circuit(e.g., switch 732 or switch 736) can be opened and the switches for thecorresponding filter (e.g., the switches 740 and 746, or the switches744 and 738) can be closed.

Example Dynamic Multi-Stage Multiplexer Configuration Process

FIG. 8 presents a flowchart of an embodiment of a dynamic multi-stagemultiplexer configuration process 800. As with the processes 500 and600, the process 800 can be implemented by any system that can configurea multi-stage multiplexer (such as the triplexer 710) based, at least inpart, on the frequency band or bands being used to communicate withanother device, such as a base station. For example, the process 800 maybe performed by a baseband processor 40, a call processor 212, a lookuptable 216, a control 18, or a processor 20, to name a few. Although oneor more systems may implement the process 800, in whole or in part, tosimplify discussion, the process 800 will be described with respect toparticular systems. Further, although the process 800 will be describedwith respect to a two stage multiplexer, it should be understood thatthe process 800 can be adapted to be performed with respect to amultiplexer of any number of stages. For example, the process 800 can beused with a one stage, three stage, or five stage multiplexer.

The process 800 begins at the block 802 where, for example, the basebandprocessor 40 receives a control signal from a base station identifyingone or more communication frequencies. In some cases, the control signalis received by the triplexer 710, or a controller (not shown) includedin the triplexer 710. In some embodiments, the block 802 may include oneor more of the embodiments described with respect to the block 502.

At block 804, the baseband processor 40 (or other controller of thetriplexer 710) configures a first filter stage based at least in part onthe one or more communication frequencies. Configuring the first filterstage may include opening or closing one or more switches between aninput port of the triplexer 710 and filters of the first filter stage.As previously described, the first filter stage may include the filtersbetween the input port 302 and a second filter stage. For example, thefilters 722 and 724 may be included in the first filter stage. However,in some cases, at least some of the filters of the first filter stage(such as the filter 722) may be connected between the input port 302 anda switch bank 406 and/or load bank 430.

In some cases, configuring the first filter stage may includeconfiguring the switch bank 406 to connect a filter from the firstfilter stage (such as the filter 722) to a particular load included inthe load bank 430. In some embodiments, the block 804 may be optional oromitted because, for example, the filters are configured to filterparticular frequencies prior to processing by the second stage offilters.

At block 806, the baseband processor 40 configures a second filter stagebased at least in part on the one or more communication frequencies. Thesecond filter stage may include filters (such as the filters 726 and728) located between the first filter stage and a switch bank 406.Configuring filters of the second filter stage may include connecting ordisconnecting filters from the second filter stage to one or more signalpaths of the triplexer 710. For example, the switch 734 may be opened todisconnect the filter 726 from the signal path. Advantageously, incertain embodiments, disconnecting particular filters may affect theisolation and insertion loss of other signal paths within the triplexer710 enabling the triplexer to be configured to process a greater numberof signal paths than traditional triplexers.

Further, configuring filters of the second filter stage may includeconnecting or disconnecting different load circuits included in the loadbank 430 via the switch bank 406. As with the disconnecting of thedifferent filters, the connecting of particular load circuits to thefilters of the second filter bank may affect the isolation and insertionloss of signal paths within the triplexer 710 enabling the triplexer tobe configured to process a greater number of signal paths thantraditional triplexers.

At block 808, the baseband processor 40 configures a bypass circuit(such as the bypass circuit 730) based at least in part on the controlsignal. Configuring the bypass circuit may include connecting ordisconnecting the bypass circuit from a signal path via, for example,the switch 732. Alternatively, or in addition, configuring the bypasscircuit may include connecting the bypass circuit to a particular loadcircuit in the load bank 430 via the switch bank 406. In someembodiments, the triplexer may include multiple bypass circuits. In somesuch cases, the block 808 may include configuring the plurality ofbypass circuits based on the frequencies identified by the controlsignal. In some cases, one bypass circuit may be connected and anothermay be disconnected from the signal paths of the triplexer 710. Otherconfigurations of the bypass circuits are possible. For example, bothbypass circuits may be connected to signal paths of the triplexer 710,but each bypass circuit may be connected to a different load circuit.

Although omitted to simplify the FIG. 8, the process 800 may include oneor more of the processes described with respect to FIGS. 5 and 6. Forexample, the process 800 may include determining whether the controlsignal identified one or a plurality of frequencies or frequency bands.If a single frequency is identified, the second filter bank may bedeactivated. For example, if the single frequency is below 960 MHz, inthe example of FIG. 7A, the filter 722 may be used and the remainingfilters may be disconnected. Disconnecting the remaining filters mayinclude connecting the remaining filters to an open load and/or notconnecting the remaining filters to an output port 404.

Further, the process 800 may include determining whether one or morefilters identified based on the control signal are supported by thetriplexer 710. If a frequency is not supported by the triplexer 710, thebypass path 730 may be connected to the signal path, and the remainingsignal paths may be disconnected.

TERMINOLOGY

It is to be understood that not necessarily all objects or advantagesmay be achieved in accordance with any particular embodiment describedherein. Thus, for example, those skilled in the art will recognize thatcertain embodiments may be configured to operate in a manner thatachieves or optimizes one advantage or group of advantages as taughtherein without necessarily achieving other objects or advantages as maybe taught or suggested herein.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” The term “coupled” is used to refer tothe connection between two elements, the term refers to two or moreelements that may be either directly connected, or connected by way ofone or more intermediate elements. Additionally, the words “herein,”“above,” “below,” and words of similar import, when used in thisapplication, shall refer to this application as a whole and not to anyparticular portions of this application. Where the context permits,words in the above Detailed Description using the singular or pluralnumber may also include the plural or singular number respectively. Theword “or” in reference to a list of two or more items, that word coversall of the following interpretations of the word: any of the items inthe list, all of the items in the list, and any combination of the itemsin the list.

The above detailed description of embodiments of the inventions are notintended to be exhaustive or to limit the inventions to the precise formdisclosed above. While specific embodiments of, and examples for, theinventions are described above for illustrative purposes, variousequivalent modifications are possible within the scope of theinventions, as those skilled in the relevant art will recognize. Forexample, while processes or blocks are presented in a given order,alternative embodiments may perform routines having steps, or employsystems having blocks, in a different order, and some processes orblocks may be deleted, moved, added, subdivided, combined, and/ormodified. Each of these processes or blocks may be implemented in avariety of different ways. Also, while processes or blocks are at timesshown as being performed in series, these processes or blocks mayinstead be performed in parallel, or may be performed at differenttimes.

The teachings of the inventions provided herein can be applied to othersystems, not necessarily the system described above. The elements andacts of the various embodiments described above can be combined toprovide further embodiments.

Conditional language used herein, such as, among others, “can,” “might,”“may,” “e.g.,” and the like, unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain embodiments include, while other embodiments donot include, certain features, elements and/or states. Thus, suchconditional language is not generally intended to imply that features,elements and/or states are in any way required for one or moreembodiments or that one or more embodiments necessarily include logicfor deciding, with or without author input or prompting, whether thesefeatures, elements and/or states are included or are to be performed inany particular embodiment.

Disjunctive language such as the phrase “at least one of X, Y, or Z,”unless specifically stated otherwise, is otherwise understood with thecontext as used in general to present that an item, term, etc., may beeither X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z).Thus, such disjunctive language is not generally intended to, and shouldnot, imply that certain embodiments require at least one of X, at leastone of Y, or at least one of Z to each be present.

Unless otherwise explicitly stated, articles such as “a” or “an” shouldgenerally be interpreted to include one or more described items.Accordingly, phrases such as “a device configured to” are intended toinclude one or more recited devices. Such one or more recited devicescan also be collectively configured to carry out the stated recitations.For example, “a processor configured to carry out recitations A, B andC” can include a first processor configured to carry out recitation Aworking in conjunction with a second processor configured to carry outrecitations B and C.

While certain embodiments of the inventions have been described, theseembodiments have been presented by way of example only, and are notintended to limit the scope of the disclosure. Indeed, the novel methodsand systems described herein may be embodied in a variety of otherforms; furthermore, various omissions, substitutions and changes in theform of the methods and systems described herein may be made withoutdeparting from the spirit of the disclosure. The accompanying claims andtheir equivalents are intended to cover such forms or modifications aswould fall within the scope and spirit of the disclosure.

What is claimed is:
 1. A method of dynamically configuring amultiplexer, the method comprising: receiving a control signal from abase station, the control signal identifying at least one communicationfrequency; determining whether the control signal identifies a pluralityof communication frequencies; in response to determining that thecontrol signal identifies the plurality of communication frequencies:configuring a filter bank of the multiplexer based at least in part onthe plurality of communication frequencies, the filter bank including aplurality of filters; determining whether the plurality of communicationfrequencies are associated with a set of special carrier aggregationbands; and in response to determining that the plurality ofcommunication frequencies are associated with the set of special carrieraggregation bands: selecting a load circuit from a plurality of loadcircuits included in the multiplexer based on the plurality ofcommunication frequencies; and connecting a bypass path included in themultiplexer to the load circuit.
 2. The method of claim 1 whereinconfiguring the filter bank includes: accessing a lookup table toidentify switch configurations for a switch bank of the multiplexer; andconfiguring the switch bank based on the identified switchconfigurations.
 3. The method of claim 1 wherein, in response todetermining that the plurality of communication frequencies areassociated with the set of special carrier aggregation bands, the methodfurther includes disconnecting a remainder of additional bypass pathsincluded in the multiplexer.
 4. The method of claim 1 wherein the set ofspecial carrier aggregation bands include a plurality of frequency bandswith less than a threshold frequency spacing between the bands.
 5. Themethod of claim 4 wherein the threshold frequency spacing is 150megahertz.
 6. The method of claim 1 wherein, in response to determiningthat the control signal identifies the plurality of communicationfrequencies, the method further includes: determining whether theplurality of communication frequencies are associated with a set ofcommon carrier aggregation bands; and in response to determining thatthe plurality of communication frequencies are associated with the setof common carrier aggregation bands, disconnecting the bypass path. 7.The method of claim 6 wherein the set of common carrier aggregationbands include a plurality of frequency bands with greater than athreshold frequency spacing between the bands.
 8. The method of claim 7wherein the threshold frequency spacing is 150 megahertz.
 9. The methodof claim 6 wherein the set of common carrier aggregation bands include aplurality of frequency bands with an isolation requirement ofapproximately 20 decibels.
 10. The method of claim 1 wherein, inresponse to determining that the control signal identifies a singlecommunication frequency, the method further includes: connecting a firstfilter corresponding to the single communication frequency from thefilter bank to an output port of the multiplexer; and disconnectingremaining signal paths within the multiplexer.
 11. The method of claim10 wherein the remaining signal paths include a first signal path thatincludes a second filter that does not correspond to the singlecommunication frequency and a second signal path that corresponds to thebypass path.
 12. The method of claim 1 wherein, in response todetermining that the control signal identifies an unsupported signal,the method further includes: deactivating the filter bank; connectingthe bypass path to an output port of the multiplexer; and disconnectingremaining bypass paths of the multiplexer.
 13. A method of dynamicallyconfiguring a multi-stage multiplexer, the method comprising: receivingat a multiplexer a control signal from a baseband processor, the controlsignal identifying a frequency band; configuring a filter bank of themultiplexer based at least in part on the control signal by: configuringa first filter stage of the filter bank based at least in part on thefrequency band, the first filter stage configured to filter a signal toobtain a partially filtered signal; and configuring a second filterstage of the filter bank based at least in part on the frequency band,the second filter stage configured to filter the partially filteredsignal to obtain a filtered signal of the frequency band; andconfiguring a bypass circuit of the multiplexer based at least in parton the control signal.
 14. The method of claim 13 wherein the controlsignal is based on a second control signal received from a base station.15. The method of claim 13 wherein the bypass circuit is part of thesecond filter stage.
 16. The method of claim 13 further comprisingdetermining based at least in part on the control signal whether themultiplexer is to operate in a carrier aggregation mode.
 17. The methodof claim 16 wherein, in response to determining that the multiplexer isto operate in a carrier aggregation mode, configuring the bypass circuitincludes disconnecting the bypass circuit from an operational signalpath of the filter bank.
 18. The method of claim 16 wherein, in responseto determining that the multiplexer is to operate in a carrieraggregation mode, configuring the bypass circuit includes connecting thebypass circuit to a filter from the first filter stage.
 19. The methodof claim 13 wherein, in response to determining based at least in parton the control signal that the multiplexer is to operate in a bypassmode, configuring the second filter stage includes disconnecting thesecond filter stage from the first filter stage.
 20. The method of claim13 further comprising: selecting a set of load circuits from a pluralityof available load circuits included in the multiplexer based at least inpart on the control signal; and connecting a set of filter output pathsfrom the filter bank to the set of load circuits.